OBJECTIVES: 1. Development of a foreign body forceps for use in vitreous surgery to eliminate the need for multiple instruments. 2. The ever increasing need for and use of bright light sources for examinations of the eye and documentation of eye surgery creates concern about potential light hazards. As it is now known that the blue components of the light are the most dangerous ones, they will be eliminated by appropriate filters. In addition, an attempt will be made to find optimum values for light requirements during surgery as well as means to adequately document with photography the intraocular events despite the altered light composition. 3. Documentation of intraocular findings with still photography during surgery is very difficult because of lack of adequate photographic systems attached to the operating microscope. Further improvement on the first modification will be sought. 4. A Zeiss photo slit lamp will be simplified to provide adequate lighting for high magnification and high speed photography. 5. Extension of the study of the effects of steroids on intraocular proliferation by selection of the most appropriate steroid. Also, timing and length of therapy, dosage of steroids and the possibility of combining long acting with short acting steroids will be evaluated.